Question

A piece of legacy code I’m running that does some oracle SQL is violating a constraint called REF_REQUEST.

I look up this constraint by doing:

select * from all_constraints where constraint_name='REF_REQUEST'

This tells me that the constraint_type is ‘R’, and it gives me the table name of CORRESPONDENCE.

However, I still don’t know… what value I’m missing from CORRESPONDENCE, or where I’m trying to insert that is causing the issue, and what column is relevant from each. How can I learn this information by querying the dB?

Answer 1

Use get_ddl method in dbms_metadata package to get more details about the constraint

SELECT CAST(DBMS_METADATA.GET_DDL('CONSTRAINT','REF_REQUEST','CERTIFICATION') AS VARCHAR2(4000)) 
FROM DUAL

That should tell you what columns the constraint is acting on

---

One of the overloaded methods accepts the schema name, so you can pass it as a parameter.

DBMS_METADATA.GET_DDL (
object_type     IN VARCHAR2,
name            IN VARCHAR2,
schema          IN VARCHAR2 DEFAULT NULL,
version         IN VARCHAR2 DEFAULT 'COMPATIBLE',
model           IN VARCHAR2 DEFAULT 'ORACLE',
transform       IN VARCHAR2 DEFAULT 'DDL')
RETURN CLOB;

Further reading:

• Oracle documentation on dbms_metadata.get_xxx subprograms